Washington's top envoy in Hong Kong might have thought he was being careful when he said on Tuesday that the US would not take sides when it came to the city's democratic development.

But Clifford Hart's comments in his first public speech in his new role managed to reignite Beijing's anger.

The Ministry of Foreign Affairs yesterday again told the US to stay out of Hong Kong affairs.

While Hart said Washington supported "genuine universal suffrage" but had "no prescription" when it came to democratic development, the Ministry of Foreign Affairs said no other country should have any say in the city's constitutional development.

"The issue of political development is Hong Kong's internal affair, and China's internal politics," ministry spokesman Hong Lei said. "No countries should make irresponsible remarks. We request that the relevant countries align their words with their actions, and do more that helps Hong Kong become prosperous and stable."

The Beijing-loyalist Wen Wei Po published an editorial saying Hart could be "facing a gloomy ending if he continues meddling in Hong Kong's political development". It said: "Clifford Hart has ignored a warning from the Chinese government and is blatantly intervening in the city's political development. Such an act is a violation of the Vienna Convention on Consular Relations."

It was referring to the treaty that forbids diplomats from interfering in the internal affairs of host states. In May, the Foreign Ministry also quoted the document in a warning to Hart's predecessor, Stephen Young.

The daily pointed an accusing finger at an invitation the consulate posted on Facebook on the 50th anniversary of Martin Luther King's "I have a dream" speech, asking people what their dream was. Most of those who posted replies said they wanted an independent Hong Kong.

This article appeared in the South China Morning Post print edition as Beijing blasts US envoy anew on suffrage